A row broke out between Warsaw and London after British Prime Minister David Cameron told the BBC Jan. 5 that immigrants from EU countries working in Britain should not receive social benefit payments for children left behind in their home countries. Cameron singled out immigrants from Poland as an example.

Warsaw reacted instantly. Polish Foreign Minister Radosław Sikorski said that Poles worked in Britain legally, paid taxes there and were entitled to claim benefits just like all other people with jobs. Polish Prime Minister Donald Tusk described the British leader’s language as “inappropriate” and discussed the matter with Cameron on the phone. Jarosław Kaczyński, the leader of Poland’s opposition Law and Justice (PiS) party, called Downing Street as well. Neither the details of his conversation nor that between Cameron and Tusk have been revealed.

Polish left-wing opposition leader Leszek Miller wrote a letter to Ed Miliband, the head of Britain’s opposition Labour Party, and to ex-British prime minister Tony Blair, urging them to stand up against “conservative madness which, in order to appeal to a certain group of voters, attacks and stigmatizes a national group—Poles in this case—and perverts the way in which the European Union is supposed to function.”

Polish politicians also noted that Cameron was openly calling for changes to EU law. Under current rules, immigrants from one EU country who reside and pay social security contributions in another member state can claim child benefits even if their children live abroad. Any change to these rules would require new international agreements or changes to European Union treaties. Sikorski has made it clear that Poland will veto any attempt at introducing what he called discriminatory changes to EU rules.

The benefits Cameron was referring to are paid out to around 24,000 immigrant families from EU countries. In total, such families have around 40,000 children and two-thirds of them, almost 27,500, are Polish.